We need to find out how many adults must the brand manager survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage.
From the given data we know that our confidence level is 90%. From Standard Normal Table we know that the critical level at 90% confidence level is 1.645. In other words, 
.
We also know that E=5% or E=0.05
Also, since, 
is not given, we will assume that =0.5. This is because, the formula that we use will have 
in the expression and that will be maximum only when =0.5. (For any other value of , we will get a value less than 0.25. For example if, is 0.4, then 
and thus, 
.).
We will now use the formula
We will now substitute all the data that we have and we will get
which can approximated to n=271.
So, the brand manager needs a sample size of 271
Answer:
3/6 and 1/2
Step-by-step explanation:
If you divide each side of the fraction by 2 it will give you 1/2.
All of them are wrong its 91 but if you want click or circle 90
Answer:
Yes
Step-by-step explanation:
Many students gets confused with these exponential problems, they often get misguided but understand that there is nothing to be confused of.
When you have a negative number, you just take the reciprocal of the whole exponent number.
What is a reciprocal?
Let's take an integer for example, let's take the number 3.
The reciprocal for 3 is (1/3)
Let's take an other number, let's take 2/3
The reciprocal for 2/3 is (3/2)
In conclusion, we just reverse the denominator and the numerator or just switch it.
We take 3 as (3/1) and that is the reason, the reciprocal would be (1/3)
Now, coming to the negative integers. Taking an example:
(2)⁻¹
This would be become (1/2¹) = (1/2)
Hence, the result of a negative integer is positive but would be a fraction.
Hope I helped!
The area of the room must equal the sum of the areas of the tiles...
20*30=n(2*3)
600=6n
n=100
So 100 tiles are needed.
